AlGaN/GaN heterostructure devices have small capacitances during device switching, which originate partially from high electron mobility and because only majority carriers (e.g. electrons) are responsible for the on and off switching of the device. Any additional parts of the device such as a body diode ideally should not interfere with these material and device characteristics. Furthermore, the threshold voltage of a body diode leads directly to losses which are especially important for low voltage devices. Therefore Schottky diodes are typically preferred to be used as body diodes for low voltage devices because Schottky diodes have a generally lower threshold voltage compared to semiconductor diodes. Other conventional solutions to achieve low threshold voltage are the implementation of an additional MOS-gated diode (MGD), or an additional quasi-body diode buried in the bulk below the device. However, the MGD approach requires about 15% additional space and may further require an additional gate stack process in order to adjust the threshold voltage of the MGD gate close to about 0 V, which is typically not the same threshold voltage needed in power applications. A quasi-body diode buried in the bulk below an AlGaN/GaN heterostructure device can limit the breakdown voltage of the device.